/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkImplicitCylinderWidget.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
// .NAME vtkImplicitCylinderWidget - 3D widget for manipulating an infinite cylnder
// .SECTION Description
// This 3D widget defines an infinite cylinder that can be
// interactively placed in a scene. The widget is assumed to consist
// of four parts: 1) a cylinder contained in a 2) bounding box, with a
// 3) cylinder axis, which is rooted at a 4) center point in the bounding
// box. (The representation paired with this widget determines the
// actual geometry of the widget.)
//
// To use this widget, you generally pair it with a vtkImplicitCylinderRepresentation
// (or a subclass). Variuos options are available for controlling how the
// representation appears, and how the widget functions.

// .SECTION Event Bindings
// By default, the widget responds to the following VTK events (i.e., it
// watches the vtkRenderWindowInteractor for these events):
// <pre>
// If the cylinder axis is selected:
//   LeftButtonPressEvent - select normal
//   LeftButtonReleaseEvent - release (end select) normal
//   MouseMoveEvent - orient the normal vector
// If the center point (handle) is selected:
//   LeftButtonPressEvent - select handle (if on slider)
//   LeftButtonReleaseEvent - release handle (if selected)
//   MouseMoveEvent - move the center point (constrained to plane or on the
//                    axis if CTRL key is pressed)
// If the cylinder is selected:
//   LeftButtonPressEvent - select cylinder
//   LeftButtonReleaseEvent - release cylinder
//   MouseMoveEvent - increase/decrease cylinder radius
// If the outline is selected:
//   LeftButtonPressEvent - select outline
//   LeftButtonReleaseEvent - release outline
//   MouseMoveEvent - move the outline
// If the keypress characters are used
//   'Down/Left' Move cylinder away from viewer
//   'Up/Right' Move cylinder towards viewer
// In all the cases, independent of what is picked, the widget responds to the
// following VTK events:
//   MiddleButtonPressEvent - move the cylinder
//   MiddleButtonReleaseEvent - release the cylinder
//   RightButtonPressEvent - scale the widget's representation
//   RightButtonReleaseEvent - stop scaling the widget
//   MouseMoveEvent - scale (if right button) or move (if middle button) the widget
// </pre>
//
// Note that the event bindings described above can be changed using this
// class's vtkWidgetEventTranslator. This class translates VTK events
// into the vtkImplicitCylinderWidget's widget events:
// <pre>
//   vtkWidgetEvent::Select -- some part of the widget has been selected
//   vtkWidgetEvent::EndSelect -- the selection process has completed
//   vtkWidgetEvent::Move -- a request for widget motion has been invoked
//   vtkWidgetEvent::Up and vtkWidgetEvent::Down -- MoveCylinderAction
// </pre>
//
// In turn, when these widget events are processed, the vtkImplicitCylinderWidget
// invokes the following VTK events on itself (which observers can listen for):
// <pre>
//   vtkCommand::StartInteractionEvent (on vtkWidgetEvent::Select)
//   vtkCommand::EndInteractionEvent (on vtkWidgetEvent::EndSelect)
//   vtkCommand::InteractionEvent (on vtkWidgetEvent::Move)
// </pre>
//

// .SECTION See Also
// vtk3DWidget vtkImplicitPlaneWidget

#ifndef vtkImplicitCylinderWidget_h
#define vtkImplicitCylinderWidget_h

#include "vtkInteractionWidgetsModule.h" // For export macro
#include "vtkAbstractWidget.h"

class vtkImplicitCylinderRepresentation;
class vtkInteractionCallback;

class VTKINTERACTIONWIDGETS_EXPORT vtkImplicitCylinderWidget : public vtkAbstractWidget
{
  friend class vtkInteractionCallback;

public:
  // Description:
  // Instantiate the object.
  static vtkImplicitCylinderWidget *New();

  // Description:
  // Standard vtkObject methods
  vtkTypeMacro(vtkImplicitCylinderWidget,vtkAbstractWidget);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Specify an instance of vtkWidgetRepresentation used to represent this
  // widget in the scene. Note that the representation is a subclass of vtkProp
  // so it can be added to the renderer independent of the widget.
  void SetRepresentation( vtkImplicitCylinderRepresentation *rep );

  // Descritpion:
  // Disable/Enable the widget if needed.
  // Unobserved the camera if the widget is disabled.
  void SetEnabled(int enabling);

  // Description:
  // Return the representation as a vtkImplicitCylinderRepresentation.
  vtkImplicitCylinderRepresentation *GetCylinderRepresentation()
    {return reinterpret_cast<vtkImplicitCylinderRepresentation*>(this->WidgetRep);}

  // Description:
  // Create the default widget representation if one is not set.
  void CreateDefaultRepresentation();

protected:
  vtkImplicitCylinderWidget();
  ~vtkImplicitCylinderWidget();

  // Manage the state of the widget
  int WidgetState;
  enum _WidgetState {Start=0,Active};

  // These methods handle events
  static void SelectAction(vtkAbstractWidget*);
  static void TranslateAction(vtkAbstractWidget*);
  static void ScaleAction(vtkAbstractWidget*);
  static void EndSelectAction(vtkAbstractWidget*);
  static void MoveAction(vtkAbstractWidget*);
  static void MoveCylinderAction(vtkAbstractWidget*);

  // Description:
  // Update the cursor shape based on the interaction state. Returns 1
  // if the cursor shape requested is different from the existing one.
  int UpdateCursorShape( int interactionState );

  // Description:
  // Handle the interaction callback that may come from the representation
  vtkInteractionCallback *InteractionCallback;
  void InvokeInteractionCallback();

private:
  vtkImplicitCylinderWidget(const vtkImplicitCylinderWidget&);  //Not implemented
  void operator=(const vtkImplicitCylinderWidget&);  //Not implemented
};

#endif
